1. Field of the Invention
The present invention relates to a method for fixation of cut up carcasses of slaughter hogs, which are suspended at their hind legs and which have been eviscerated after the cutting, during which fixation in particular the spinal column of the hog is aligned relative to the median plane of the carcass by means of a member clutching the snout of the animal, said member exerting a downwards pull to stretch out the animal during the cutting of the carcass, or for processes requiring a fixation of the carcass relative to a median plane. Moreover, the invention relates to a apparatus for carrying out the method when splitting or blankfinning the carcass.
2. Prior Art
When splitting or blankfinning carcasses by means of automatic tools it is important in order to attain a satisfactory result that the carcass is placed accurately opposite the tools and that curvatures or bendings of the spine, if any, is straightened out, if possible. A known apparatus for the centering of gutted carcasses suspended at their hind legs and which are to be backsplitted, comprises a stretching means for engaging the lower jaw. The apparatus, which is described in Danish Patent no. 139,373, moreover comprises a supporting device resting against the belly of the animal, as well as hooks clutching the hind legs of the animal close to the suspension hooks. From the specification to Danish Patent No. 144,551 an arrangement is known which comprises guiding rollers, which roll along the backbone of a carcass to be backsplitted is known. These rollers, which roll partly against the inner side of the spinal column in the abdominal cavity of the carcass, partly on the outer side, are to a certain extent able to align an obliquely suspended carcass. However, these rollers do not become effective until they have moved somewhat along the spinal column, and they have only a slight effect on the portion of the spinal column from the pelvic region to where the ribs start. If the carcass has not been correctly suspended on the carrier yoke, or separate hooks have been used which have not been inserted in the same way in the two hind legs or have a different size, so big curvatures of the spinal column may occur exactly in the area between the pelvic section and the area, where the ribs start, that when splitting the spinal bone it is not possible to attain a pure cut hitting exactly through the middle of the spinal column. The same conditions apply in blankfinning, where a pair of tools is to be taken along the dowels of the spinal column to free the muscles placed along the spinal column. Moreover, similar conditions apply, if instead of splitting the carcass a more extensive direct cutting is to be made, while the carcass is still suspended at the hind legs.
When splitting hog carcasses with a saw passed through the spinal column there is, at the beginning of the sawing, a risk that the hams of the animal will be damaged by the saw blade. On account of this risk it is common to introduce the saw at a level fairly low relative to the pelvic region, which puts a big load on the blade, as it is engaged at the same time over a very big part of its periphery. It is therefore desirable, if the hams can be spread before the cutting process starts, but this is not possible if the animals are suspended on a yoke which is common for the two legs, and if two separate hooks are used, unbalances, if any, in the suspension will be enhanced.